In addition to what Dennis intimated, the politics of compassion causes Leftist LUNCs because:
1) "The greater the distance between the giver and the receiver, the more the receiver develops a sense of entitlement" (see HERE)--fostering the dysfunction of victimization and dependency (see HERE and HERE),
Case in point:
2) The greater distance between giver and receiver, the less the giver is sensitive and responsive to the respective needs of the receiver. (see HERE) Governments, particularly centralized governments, make for very poor charitable organizations, oft leaving recipients of charity worse off than before the government stepped in. (see HERE)
Stefan Molyneux provides another perspective:
Also, I suspect that while the hearts of the majority of liberals may be in the right place when it comes to matters of compassion, other liberals are not so charitably disposed--to put it mildly.
According to Lord Acton, "Power tends to corrupt, and absolute power corrupts absolutely." Liberal politicians, like other politicians, are not immune, and have been enticed by the allure of power to not only work to expand their power base, but also stay in power by staying in office. To accomplish both within democratic systems, they have needed to attract money, influence, and votes, and they have done so by at least seeming to give people what is appealing and popular and what they want.
Liberal politicians understand that compassion has high emotional appeal and is a relative easy sell. When peddled effectively, the use of compassion and sympathy ploys have not only "bought" support and provided job security and expanded the power of politicians, it has also been used as a stick with which to beat opponents over the head. (see HERE)
Power isn't the only thing that corrupts. Selfishness also corrupts, and absolute selfishness corrupts absolutely. To some extent, the selling of compassion by politicians has been easy, particularly to a broad spectrum of opportunists. Certain bureaucrats have viewed compassion as a great way to grow government and create public jobs for themselves as well as politicians. Various non-profit and for-profit organizations have seen dollar signs in relation to potential compassion-oriented grants and contracts. Then there are some of the electorate who take advantage of public assistance and free-load off and game the system for all its worth.
In such cases (politicians, bureaucrats, and electorate alike) the foremost objective wasn't compassion, but self-interest. The priority wasn't keeping children safe, or caring for the sick, preserving the environment, helping the poor, etc. though such may have been secondary or tertiary interests. Rather, the real and primary purpose was to exploit the government for personal gain. Compassion was used and abused as an excuse or the means to achieve selfish ends, and a way to create the illusion of virtue and legitimacy.
Worse yet, the politics of compassion has moved beyond political exploitation, to actual fraud--which some have referred to as "sympathy grifting". (See HERE and HERE and HERE and HERE)
Unfortunately, while the primary motive for the majority of liberals may have been compassion, and they have acted in good faith, to a considerable extent they have been played by those acting in self-interest. They have been the victims of a remarkably skillful and elaborate bait-and-switch con. They were led to believe that they were merely feeding the hungry, caring for those in need, preserving the environment, and so forth, when in fact they were providing job security, sureing up power-bases, lining pockets, and constructing one of the most expansive government-industrial complexes in human history--which now significantly dwarfs the military-industrial complex warned against by President Eisenhower.. (See Social Services Industrial Complex. And, for an in-depth analysis of the government-industrial complex of compassion, please see also HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE and HERE)
Is it any wonder, then, that Leftist LUNCs have occurred? Since selfishness was really the main goal behind certain so-called compassionate governmental programs, then it is logical and ought to be expected that selfishness would be the result. Garbage in...garbage out. Sadly, what may seem as unintended negative consequences to those who were conned, have in reality been quite intended and welcomed by those liberals acting in their own self-interest.
There are a number of examples that could be cited, but some of the shenanigans perpetrated in relation to Obamacare are illustrative, such as the voter registration requirement for Obamacare, which many suspect is a way of further solidifying the liberal power base. (see HERE and HERE and HERE and HERE and HERE and HERE)
Selfish and power-hungry liberals aren't the only ones to blame for compassion-generated Leftist LUNCs. Compassionate liberals, themselves, have contributed to the problem, and perhaps even more so than selfish liberals, because their compassion has often been uniformed, mindless, misdirected, inane, and ultimately destructive. The good folks on the Left have errantly assumed that good and compassionate intents is what matters, rather than results, and consequently the results of their compassion has frequently been deplorable.
Few examples manifest this better than the legalization of same-sex marriage. Please see my blog post on: Same-Sex Marriage--Destructive Compassion.
The transgender and other disturbed communities haves also been ill-effected by liberal "compassion": 50 Tears of Sex-changes Mental Disorders, and Too Many Suicides
In the future, as I look at Leftist LUNCs in relation to things like liberal immigration policies, Obananomics (particularly corporate and bank bailouts and the misnamed "Economic Stimulous Package"), etc., more examples will be provided.
[Update 08/30/15: The Politics and Demographics of Food Stamp Recipients]